Field of the Invention
The present invention relates to a field of monitor technology, and more particularly to a grayscale compensation method.
Description of Prior Art
FIG. 1 illustrates an arrangement of pixel units on a display panel. The display panel 10 includes a plurality of pixel units 11, in conjunction with FIG. 2, and each pixel unit 11 includes a red sub-pixel 13, a green sub-pixel 14, a blue sub-pixel 15, and a white sub-pixel 16. Only one arrangement is given in FIG. 1, certainly, and other arrangements are feasible but are not herein enumerated. There are additional white sub-pixels arranged on the whole display panel in FIG. 1. In a panel, such an arrangement of pixel units having additional white sub-pixels raises transmissivity of a backlight, and therefore a luminance of a white pixel image also is increased. Since the contrast of the picture is heightened, the luminance of the backlight can be reduced, thereby reducing power consumption of the backlight.
When a panel having the arrangement of pixel units of FIG. 1 is analyzed, it is found that since each image data inputted to each pixel of the display panel is generally described by a grayscale data corresponding to three colors, in order not to change a resolution of a panel, there are blue (B), green (G), and red (R) grayscale data within three pixels replaced by white (W) grayscale data for every four consecutive pixels 21-24 (arrangement such as GBW, RGB, WRG, BWR) as shown in FIG. 2, which illustrates the arrangement of pixel units in a row. The pixel having a white grayscale data W can achieve satisfactory results when the panel displays, for example, landscape pictures, but a phenomenon such as a color edge, an edge blurring, or even an error, is common to be found when black texts are displayed under a white background. Although this above phenomenon can be alleviated to some degree by using a nine-point filter, the display performance is still poor. Apart from that, two line buffers are required to be used in implementation of hardware so that a cost of hardware is increased.
Thus, there is a need for providing a grayscale compensation method to solve the existing problem of the prior art.